"Muhammad Ali's funeral will take place in his hometown of Louisville, Kentucky," family spokesperson Bob Gunnell said in a statement. "The Ali family would like to thank everyone for their thoughts, prayers, and support and asks for privacy at this time."

Bob Arum, Ali's boxing promoter, said, "A true great has left us. Muhammad Ali transformed this country and impacted the world with his spirit. His legacy will be part of our history for all time."

"We lost a giant today. Boxing benefitted from Muhammad Ali's talents but not nearly as much as mankind benefitted from his humanity," professional boxer Manny Pacquiao said in a statement. "Our hearts and prayers go out to the Ali family. May God bless them."

The United States Olympic Committee also released a statement following Ali's death. "The USOC is deeply saddened to hear that the sports world has lost one of its most iconic figures in Muhammad Ali," CEO Scott Blackmun said. "As we reflect his accomplishments and victories, we are proud to call Ali not only a member of Team USA, but an Olympic champion. With unparalleled grit and determination, he left a legacy that will continue to inspire generations of Americans for years to come. Our thoughts and prayers are with his family and friends during this difficult time."

Ali's longtime friend, Dionne Warwick, also shared heartfelt condolences. "So sorry to hear of another dear friend making his transition," she said in a statement obtained by ET. "He will always be The Greatest and will be remembered with wonderful memories shared….My sincere condolences go out to his family. Rest in peace, my friend."

Since news broke, many athletes, celebritie and public figures have been paying their respects to the three-time World Heavyweight Champion on social media, with many sharing their own memories and photos with Ali.

Mike Tyson shared one such pic on Twitter, writing, "God came for his champion. So long great one. @MuhammadAli #TheGreatest #RIP."

Floyd Mayweather shared a length, heartfelt message via Instagram, noting just how important Ali was to his career. "Today my heart goes out to a pioneer, a true legend, and a hero by all means! Not a day went by entering the gym that I didn't think of you," he wrote. "Your charisma, your charm and above all, your class are all of the elements that will be greatly missed by myself and the world."

Comedian Billy Crystal, who befriended the boxing legend after imitating him in his first television appearance in 1974, shared an essay he wrote on Ali -- who called Crystal "Little Brother" -- for USA Today Sports back in 2010.

"He once asked if I’d like to run with him on a golf course. He loved to run there for privacy," Crystal remembered. "Sure, I said, but when he told me where we would run, I told him they didn’t allow Jews there and I couldn’t go. He got angry. 'They don’t allow Jews? I’m a Muslim and they allow me! I will never run there again, little brother, I promise you.' And he didn’t. That was the Ali I will never forget."

Soccer star Pele shared a touching tribute as well, along with a photo of him greeting Ali. "The sporting universe has just suffered a big loss," he wrote in the caption, which was also translated into Spanish. "Muhammad Ali was my friend, my idol, my hero. We spent many moments together and always kept a good connection throughout the years. The sadness is overwhelming. I wish him peace with God. And I send love and strength to his family."